Cartons and method of forming same



E. J. DEWHURST CARTONS AND METHOD OF FORMING SAME Oct. 15, 1963 Filed Jan. 2, 1962 FIG.

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United States Patent Office 3,106,876 Patented Oct. 15, 1963 This invention relates to a method of forming cartons and to improvements in cartons used for the packaging of powdered or granular materials.

it is, of course, desirable to employ in the manufacture of cartons of this kind, box-board material as light as is practicable so as to achieve substantial economy as compared with the use of a corresponding amount of thicker board. A dific-ulty, however, presents itself, emphasized particularly when employing what are known as giant size cartons, for the reason that when a thin board is employed the side walls of the carton, because of their expanse, tend to bulge under the weight of the body of granular material carried therein. Consequently, this poses problems in shipping and storage of cartons which do not then present flat planar sides enabling the cartons to pack closely side by side. Of course, this dilficulty applies to smaller size cartons as well and poses a further difiiculty in that due to the bulging effect thus produced on filling of the cartons, the handling of the cartons often promotes what may be termed a bellows efieet, ire. an inward and outward movement of the side walls due to shifting of its load under handling pressure whereby powdered or granular material contained therein is caused to sift from the container with consequent undesired effects.

The method of the present invention and the package as produced thereby enables the use of thin box-board material for packages of this kind While completely eliminating bulging of the under side walls under weight of the packaged granular material so that several advantages accrue. On the one hand, a filled package having absolutely flat planar sides is shipped. On the other hand, greater vertical strength is produced in the carton as to facilitate sealing of the top and bottom flaps in the compression of the sealing machines. Any shifting of the content caused by bellows effect is avoided while finally there is a saving in the corrugated shipping cartons containing the packaged material since the elimination of any bulge in the carton has enabled the production of a smaller shipping carton to contain the same number of packages with a saving of approximately oneeighth the material of the corrugated shipping cartons. The advantages of the invention are achieved in a very simple way employing one-piece carton blanks and adding slightly more material thereto than the ordinary carton blank, the small cost of which is more than offset by the use of the lighter box-board material while waste in cutting the blanks is maintained at an absolute minimum by interlocking the blanks in the cutting operation. Moreover, the improved carton of the present invention may be formed economically from the blank in a simple manner.

The method of formation of the improved carton embodies forming a blank of four rectangular hingedly connected side walls with end wall flaps, designed to be set up as a cubic container having two opposed side walls narrower than the other two, and including with said blank a rectangular web of stock hingedly connected to and projecting laterally from a free edge of said blank, adjacent to one of said narrower walls, forming said web with hinge lines adjacent to side extremities thereof, parallel with one another and parallel with said free edge of said blank as to form inner and outer gluing tabs along two opposed edges of said web while forming between said tabs, a partition element substantially equal in width to the width of one of the narrower side walls of the carton, applying adhesive to a surf-ace of the inner tab and to the opposite surface of said outer tab, folding said narrower wall of the carton adjacent to said web inwardly to overlie a portion of the adjacent wider side wall, causing said adhesive coated surface of said inner tab to adhere thereto, while exposing the adhesive coated surface of said other tab, detaching said web from hinged connection with said blank, and folding the blank inwand from its opposite free edge to overlie said web and to cause the remain-ing overlying wide panel to adhere to the exposed adhesive surface of said outer tab and hingedly connecting the edge of said latter wide panel to the now adjacent narrower side wall whereby said partition is secured between the opposed wider walls of said blank and forms a transverse partition extending therebetween and substantially parallel to the narrower side Walls when said blank is set up to cubic carton form.

The improved carton of the present invention, therefore, embodies a trmsverse partition anchored to two opposed corresponding Wide side walls of a carton intermediate the peripheral edges thereof as to extend substantially parallel to the narrower side walls thereof when the carton is set up and thus to retain the wide side walls against bulging under the pressure of contained granular or similar material. It also embodies further more specific features as will be clearly understood from a'consideration of the following detailed specification takenin conjunction with the accomyanying drawings, inwhich,

FIG. 1 is a plan view of a blank for forming the carton of the present invention illustrating in dotted lines a portion of an adjacent carton to show the general manner in which carton blanks are preferably produced.

FIG. 2 is a perspective view of a carton blank according to the present invention.

FIG. 3 is a view similar to FIG. 2 but showing a wall of the carton folded as in the first step of forming the carton.

FIG. 4 is a view of the carton blank in a further folding operation during the formation of the carton.

FIG. 5 shows the blank completely folded and secured as a final carton forming unit.

FIG. 6 is a perspective view of the formed cart-on with the side walls set up prior to the inward folding of the top and bottom end flaps; and

FIG. 7 is a perspective view of a carton completely set up with part of two side walls broken away to show an alternative and preferred form of partition therewithin.

Referring to the drawings, A indicates a carton blank in accordance with the present invention and which is made up of normal elements for a rectangular cubic carton employing wide corresponding side walls 10 and 11 and narrower corresponding side walls 12 and .13 joined in normal manner by hinging lines and including end flaps for closing the ends of the carton. The carton also includes a side wall gluing flap 14 which is adapted to underlie the side wall 13 and is secured thereto when the carton is formed. According to the present invention, a web of box-board material 15 is included as part of the blank, which web is of less length than the length of the side walls of the carton. This web is formed in hinged connection with the free pcripheral edge '16 of the blank which in preferred form coincides with the free edge of side wall 13. Preferably the web 15 is connected to side wall 13 by the weakened perforated lines 17 and 18 and is die-out as at 19 therebetween.

The web is scored along the lines and 21 in spaced relation to the outer side extremities thereof to form the spaced apart gluing tabs 22 and 23 respectively at its side edges, and to form therebetween a partition element 24 of a width substantially coinciding to the width of one of the narrower side walls 12 and '13 of the carton so that when the carton is finally formed, it includes between the wide side walls 10 and 11 a reinforcing partition as to hold these walls against bulging when the contents, i.e. granular material or the like, is introduced thereto.

The carton is very readily formed by applying adhesive to an exposed surface of the gluing tab 22 and applying adhesive to the opposite surface, i.e. reversed side, of glue tab 23 and the surface of gluing flap 14 of panel 10 corresponding to the coated surface of tab 23. The blank is then folded along the hinge line from the position of FIG. 2 to the position shown in FIG. 3 to cause side wall 13 partially to overlie side wall 11 and to cause web 15 to overlie an area of side wall 11. The web is subjected to pressure to cause the adhesive on glue tab 22 to adhere to the corresponding underlying area of side wall 11 which is at a location adjacent to the longitudinal center line of side wall 11. By suitable means, such as a knife, the weakened hinge connections 17 and 18 of web 15 are severed which detaches the web from side wall 13 and which, due to the tension of the folded hinge connection along fold line 25, will tend to rise upwardly (FIG. 4). Side wall 10 is then folded inwardly along hinge line 26, as shown in FIG. 4, to cause it partially to overlie side wall 11 and web 15 and is subjected to pressure as to cause the now upwardly exposed adhesive coated surface of glue tab 23 to adhere to the inner surface of side wall 10 in an area close to the corresponding area of side wall 11 on which the glue tab 22 is located. Simultaneously, glue flap 14 is dis posed to underlie the side wall 13 which is then folded down so that the upwardly exposed adhesive surface of glue flap 14 is engaged by the now inner surface of side wall 13 along its free edge, as shown in FIG. 5. In this manner, the web is secured between the two side walls 10 and 11 and when the carton is set up, as shown in FIG. 6, it is provided with the intermediate partition 24 which serves to retain these side walls against outward bulging under load of the contained material and maintains the walls of the carton in coplanar relation.

It is preferred to form the web 15 in the manner shown in FIG. 7 generally indicated by the reference numeral 15a and wherein the partition 24a is formed with openings 24b along each of its edges by punching out the tabs 240 so that the powdered or granular contents may pass through the partition wall where necessary as well as being able to pass the partition above and below it. These marginal openings relieve the resistance of the creases of the partition when setting up the carton for filling due to the substantial reduction of the amount of creased material. Thus, the orificed web structure performs an important dual purpose.

While it is preferred to form the glue flap 14 along the outer edge of side wall 10 as shown in the figures, it will, of course, be clear that this glue fiap could be formed along the outer edge '16 of panel 13, in which case the web 15 would be hingedly connected to the outer edge of the glue flap and the sequence of folding would be slightly altered wherein the panel 13, as shown in FIG. 4, would be folded downwardly first so that the glue flap would be overlapped by the adjacent edge of panel 10.

In either case the partition 24 of the partition 24a, as the case may be, is readily and firmly located and attached between the wider side walls 10 and 11 at a point intermediate the side edges thereof as to reinforce side walls 10 and 11 and assure that the side walls will be substantially coplanar when the carton is set up.

By this means, the weight of the box-board material can be reduced by as much as approximately 37% with an approximate cost saving of 16%. It has been found that board of of an inch thickness may be reduced as much as to of an inch thickness in large size cartons, and in small size cartons from of an inch thickness to as little as of an inch thickness. It will be apparent, therefore, that the invention brings about many advantages.

What I claim as my invention is:

1. The method of forming a carton from thin paperboard stock and capable of withstanding the stress of a contained load of granulated or like material as to prevent bulging of the carton side walls which comprises forming a blank of said stock having four rectangular hingedly connected side walls with end wall flaps, designed to be set up as a cubic container having two opposed side walls narrower than the other two, and including with said blank a rectangular web of stock hingedly connected to and projecting laterally from a free edge of said blank adjacent to one of said narrower walls, forming said web with hinge lines adjacent to side extremities thereof, parallel with one another and parallel with said free edge of said blank as to form a first gluing tab along one edge of said web and a second gluing tab along the opposed edge of said web and a partition element substantially equal in width to the width of the narrower side walls of the carton, applying adhesive to a surface of said first gluing tab and to the opposite surface of said second gluing tab, folding said narrower wall of the carton, adjacent to said web, inwardly to cause said web to overlie a portion of the adjacent wider side wall and causing said adhesive coated surface of said first gluing tab to adhere thereto, while exposing the adhesive coated surface of said second gluing tab, detaching said web from hinged connection with said blank, and folding the blank inward from its opposite free edge to overlie said web and to cause the remaining overlying wide panel to adhere to the exposed adhesive surface of said second gluing tab and hingedly connecting the free edge of said latter wide panel to said narrower side wall located adjacent to said web, whereby said partition is secured between the opposed wider walls of said blank to form a transverse partition extending therebetwcen when said blank is set up to cubic carton form.

(2. The method as claimed in claim 1 including the step of forming a series of openings in said partition element at its margins beside said hinge lines.

References Cited in the file of this patent UNITED STATES PATENTS 2,706,935 Pasjack Apr. 26, 1955 2,854,181 Smith Sept. 30, 1958 2,913,967 Scriven Nov. 24, 1959 2,998,179 Zilles Aug. 29, 1961 3,018,701 Keely Jan. 30, 1962 3,029,711 Griese Apr. 17, 1962 

1. THE METHOD OF FORMING A CARTON FROM THIN PAPERBOARD STOCK AND CAPABLE OF WITHSTANDING THE STRESS OF A CONTAINED LOAD OF GRANULATED OR LIKE MATERIAL AS TO PREVENT BULGING OF THE CARTON SIDE WALLS WHICH COMPRISES FORMING A BLANK OF SAID STOCK HAVING FOUR RECTANGULAR HINGEDLY CONNECTED SIDE WALLS WITH END WALL FLAPS, DESIGNED TO BE SET UP AS A CUBIC CONTAINER HAVING TWO OPPOSED SIDE WALLS NARROWER THAN THE OTHER TWO, AND INCLUDING WITH SAID BLANK A RECTANGULAR WEB OF STOCK HINGEDLY CONNECTED TO AND PROJECTING LATERALLY FROM A FREE EDGE OF SAID BLANK ADJACENT TO ONE OF SAID NARROWER WALLS, FORMING SAID WEB WITH HINGE LINES ADJACENT TO SIDE EXTREMITIES THEREOF, PARALLEL WITH ONE ANOTHER AND PARALLEL WITH SAID FREE EDGE OF SAID BLANK AS TO FORM A FIRST GLUING TAB ALONG ONE EDGE OF SAID WEB AND A SECOND GLUING TAB ALONG THE OPPOSED EDGE OF SAID WEB AND A PARTITION ELEMENT SUBSTANTIALLY EQUAL IN WIDTH TO THE WIDTH OF THE NARROWER SIDE WALLS OF THE CARTON APPLYING ADHESIVE TO A SURFACE OF SAID FIRST GLUING TAB AND TO THE OPPOSITE SURFACE OF SAID SECOND GLUING TAB, FOLDING SAID NARROWER WALL OF THE CARTON ADJACENT TO SAID WEB, INWARDLY TO CAUSE SAID WEB TO OVERLIE A PORTION OF THE ADJACENT WIDER SIDE WALL AND CAUSING SAID ADHESIVE COATED SURFACE OF SAID FIRST GLUING TAB TO ADHERE THERETO, WHILE EXPOSING THE ADHESIVE COATED SURFACE OF SAID SECOND GLUING TAB, DETACHING SAID WEB FROM HINGED CONNECTION WITH SAID BLANK, AND FOLDING THE BLANK INWARD FROM ITS OPPOSITE FREE EDGE TO OVERLIE SAID WEB AND TO CAUSE THE REMAINING OVERLYING WIDE PANEL TO ADHERE TO THE EXPOSED ADHESIVE SURFACE OF SAID SECOND GLUING TAB AND HINGEDLY CONNECTING THE FREE EDGE OF SAID LATTER WIDE PANEL TO SAID NARROWER SIDE WALL LOCATED ADJACENT TO SAID WEB, WHEREBY SAID PARTITION IS SECURED BETWEEN THE OPPOSED WIDER WALLS OF SAID BLANK TO FORM A TRANSVERSE PARITION EXTENDING THEREBETWEEN WHEN SAID BLANK IS SET UP TO CUBIC CARTON FORM. 